Spinal Cord Anatomy - Spinal Segment Features
• Cervical - Large & oval in shape, slender posterior horns, broad anterior horns.
• Thoracic - Smaller & circular in shape, slender posterior + anterior horns, & lateral horns.
• Lumbar - Larger pyramidal shape & thicker gray matter, bulbous & short horns.
• Sacral - Small & quadrilateral shape. Ovoid massive posterior & anterior horns.
By @rev.med
#Spinal #Cord #Anatomy #Segments
Spinal Cord Anatomy
• Cervical (8) - Large & oval in shape, slender posterior horns, broad anterior horns.
• Thoracic (12) - Smaller & circular in shape, slender posterior + anterior horns, & lateral horns.
• Lumbar (5) - Larger pyramidal shape & thicker gray matter, bulbous & short horns.
• Sacral (5) - Small & quadrilateral shape. Ovoid massive posterior & anterior horns.
By @rev.med
#Spinal #Cord #Anatomy #neuroanatomy
Lesions of the Spinal cord - Spinal Cord Syndromes
Spinal cord lesions can result in permanent neurologic disability. It is important to quickly evaluate and treat spinal cord injury. Causes of spinal cord lesions can be divided into:
• Extrinsic Causes:
- Spinal stenosis
- Abscess
- Tumor
- Herniated disc
- Hematoma
- Stab wound and other forms of trauma
• Intrinsic Causes:
- Infarction
- Infection (e.g., poliovirus, syphilis, and HIV)
- Vitamin B12, Copper deficiency
- Syrinx
- Tumor of the spinal cord
- Autoimmune
The clinical presentation of spinal cord lesions depends on which ascending or descending fibers are involved.
Brown-Séquard Syndrome:
• Etiology:
- Knife or bullet injury
- Multiple sclerosis
• Clinical Presentation:
- Ipsilateral findings:
- Weakness
- Lower motor neuron symptoms at the level of the lesion
- Upper motor neuron symptoms below the level of the lesion
- Loss of proprioception, vibration, light touch, and tactile sense
- Contralateral findings:
- Loss of pain and temperature sensation usually 1 to 2 levels below the level of the lesion
Posterior Cord Syndrome:
• Etiology:
- Tabes dorsalis
- Friedreich ataxia
- Subacute combined degeneration
- Multiple sclerosis
• Clinical Presentation:
- Loss of proprioception and vibration sense
- Variable weakness
- Bladder dysfunction
Central Cord Syndrome:
• Etiology:
- Syringomyelia
- Intramedullary tumor
- Hyperextension injury in patients with a long history of cervical spondylosis
• Clinical Presentation:
- Loss of pain and temperature in the distribution of the level of spinal cord injury
- If the spinal cord lesion expands, it may result in:
- Weakness at the level of sensory loss (the corticospinal tract and/or the anterior horn gray matter is involved)
- Tendon reflex loss (neuronal fibers involved in deep tendon reflexes are involved)
Anterior (Ventral) Cord Syndrome:
• Etiology - Anterior spinal artery infarction which can be caused by:
- Compression injury
- Vertebral burst fracture
- Intervertebral disk herniation
- Radiation myelopathy
• Clinical Presentation:
- Typically involves tracts in the anterior two-thirds of the spinal cord which result in:
- Muscle weakness:
- The corticospinal tracts are involved
- Bilateral loss of pain and temperature sensation:
- The spinothalamic tracts are involved
- Urinary incontinence:
- The descending autonomic tracts are involved & the posterior columns are spared
Conus Medullaris:
• Etiology:
- Disc herniation
- Trauma
- Malignancy
• Clinical Presentation:
- Sphincter dysfunction
- Flaccid paralysis of the bladder and rectum
- Impotence
- Saddle anesthesia (more commonly bilateral)
- S3-S5 involvement
Cauda Equina Syndrome:
• Etiology:
- Disc herniation
- Lumbar spinal stenosis
- Malignancy
• Clinical Presentation:
- Asymmetric multiradicular pain
- Leg weakness
- Bladder and rectal sphincter paralysis
- Sensory loss
- Saddle anesthesia (more commonly unilateral)
#SpinalCord #Spinal #Cord #syndromes #lesions #differential #diagnosis #neurology
Spinal Cord Disorders - Differential Diagnosis Framework
Spinal cord neurological lesion:
Clinical findings:
• Symptoms and signs below the site of a lesion.
Corticospinal Tract Lesions:
• Bilateral findings of:
- Spastic paresis/paralysis
- Weakness
- Hyperreflexia
- Muscle spasticity
- Extensor plantar responses
- Loss of sensation at or below the site of injury
- Loss of bowel/bladder continence
• Pain reported at level of spinal cord compression
• Disruption of bladder bladder continence
• Disruption of sensation at or below the site of injury
• Gait is abnormal often- Sensory ataxia or spasticity
• Lower roots -> Cauda equina- decreased muscle tone, areflexia, loss of perianal sensation
Compression of the spinal cord:
• Herniated disc
• Epidural abscess
• Epidural hemorrhage
• Cervical spondylosis
• Epidural, intradural or intermedullary neoplasm
• Posttraumatic compression by fractured vertebral body
Non-compressive Spinal Cord Causes:
1. Demyelinating:
- Multiple sclerosis
- Transverse myelitis
- Neuromyelitis optica
- Sarcoidosis
- Radiation myelopathy
- Spinal injuries
2. Infections:
- Viral: VZV, HSV, HIV, CMV, HTLV
- Mycoplasma, Influenza, EBV, Dengue, Measles, Mumps, WNV
- Parasite: Schistosomiasis Toxoplasmosis, Neurocysticercosis
- Bacterial: Borrelia, Treponema, Listeria, TB
- Spinal abscess: hematogenous spread
- Fungal: Actinomyces, Blastomyces dermatitidis, Coccidioides, Aspergillus
3. Vascular/Blockage of the Blood Supply:
- AVM
- Antiphospholipid and other hypercoagulable states
- Hemorrhage
- Ant. Spinal artery thrombosis
4. Toxic Metabolic:
- Chemotherapy
- Radiation myelopathy
- Vit B12 and copper levels
5. Inflammatory:
- Sarcoidosis, Behcet disease
- SLE, Scleroderma, Systemic sclerosis
- MCTD, Sjogren syndrome
Cord Compression Symptoms:
• Back pain
• Weakness
• Sensory loss: Sensory level (1-5 levels below lesion)
• Bowel and bladder dysfunction
• Abnormal reflexes: Areflexia
UMN Symptoms:
• Upper extremity, lower extremity and/or bulbar region
• Weakness + slowness
• Hyperreflexia
• Spasticity
• Extensor plantar response
LMN Symptoms:
• Weakness
• Loss of muscle (atrophy)
• Muscle twitching (fasciculations)
#spinal #cord #spinalcord #disorders #diagnosis #neurology #differential #algorithm
